How long after having intercourse can i know if am pregnant or not ? can a urine test detect pregnancy ?

Yes: Urine pregnancy tests are quite accurate, but usually not until around the day you would normally start your period. If your periods are about once a month and are regular, you should be able to know you are pregnant within about 2 weeks. You get pregnant at ovulation, which is right in the middle of the cycle. Two weeks later you either start your period, or a test will be positive.